In the new review, which is a commentary of current research rather than new experimental data, the Boston Medical Center team said that research on how kids learn from interactive media has “lagged considerably behind its rate of adoption”.

Technology and 'childhood development' have a long and tricky history in scientific research. In the past studies have shown that increased time spent in front of the TV will decrease a child's development of language and social skills, for instance. Below 30 months children are not able to learn as well from TV as from interactions in real life.

But iPads - and all tablets, smartphones and other multi-use interactive screens - are fundamentally different, the team behind the study said in a press release. Tablets and other screens are multi-modal, able to switch from interactive entertainment to video and text at will, and are near-ubiquitous.

Regardless there is still no evidence to really prove that these devices can help children below pre-school age to learn - despite many apps existing to try and do exactly that.

Some of the studies the team reviewed suggested interactive screens could hurt a child’s ability to develop maths and science skills. Others said they improved literacy and were particularly beneficial to autistic children.

Dr Jenny Radesky from Developmental-Behavioural Pediatrics at Boston University said that it is possible that using technology to calm or distract a child have a negative effect:

"Heavy device use during young childhood could interfere with development of empathy, social and problem solving skills that are typically obtained by exploring, unstructured play and interacting with friends."

That was taken up pretty enthusiastically by some news sites who said the team had “called on parents to crackdown on tablet computer use”.

They haven’t, really. But in lieu of any decent evidence, Radesky says that families should not rely wholly on bright screens to educate there kids.

Something that, in the real world, seems fairly obvious.

"At this time, there are more questions than answers when it comes to mobile media. Until more is known about its impact on child development quality family time is encouraged, either through unplugged family time, or a designated family hour,” she said.